OP, I have no specific thoughts on these bikes. Just my choices many years ago and how that turned out.
1978 was my last season of bike racing; the season after my head injury. I knew going in it was my last. As the summer wound down, I started stockpiling parts for the custom I knew I was getting though I hadn't picked a builder yet. (I was pretty sure it would be Peter Mooney, a clubmate, but I hadn't talked to him yet.) I did know that this bike-to-be needed to have: clearance for big tires and fenders, cantilever brakes, be able to tour, do fast and long day rides, climb mountains and be rideable in any weather, 12 months of the year. This bike was to be a tool, pure and simple. A tool I would need to keep my sanity. (My best friend had told me how hard the years to come were going to be. She knew from her experience.)
So Peter Mooney built me a bike with moderate geometry but long chainstays (for touring), fender eyes, canto bosses. I requested a highish BB as I loved pedaling deep into corners after two seasons on a very high BB'd Fuji Professional. I also had him place the canti bosses midway between 700c and 27" so I could go with either wheel standard. (This was 1978. It was not a given that 700c would take over or even "take" outside of racing circles. And back country Maine, where I was looking for work, 700c 20 years before Al Gore was to discover the internet?)
So what I got was a bike that could do all those things. Not the best at any. It rode Saturday morning club rides with town line sprints in Santa Cruz, several crazy riders solo into the Santa Cruz mountains including down Alba Road in a January Pacific storm. I moved to the Bay area. Mt Diablo (and stealth camped on it several times, always riding out from Alameda Island). Then Seattle, rain rides, hilly rides. Overhauled the bike, went to SunTour 7-speed index. Moved to Portland. Kept riding the bike was too busy with work and marriage to give it much attention and the indexing had slipped a lot when I went from the SunTour FW it was made for to a similar but not identical SRAM FW.
Portland is a buffet table for bicycle buffs. So I atarted putting together bikes to do various things. All considerable less elegant than the Mooney, but doing its specific task better. Got "the job" and ordered my TiCycles custom. Then another, a road fix gear. The Mooney sat quietly, going out every once in a while on gravel but being mostly a farmer's market bike.
Then last winter I saw Cycle Oregon's route for this year. Perfect for a mountain fix gear like my custom - except ~30 miles of grave over three different days. I'm too old to ride that far on gravel on 28c or less tires. Rats! But the Mooney! It had horizontal dropouts, spec'd just so I could ride it fix gear if I ever wanted to. But now I needed gear ratios appropriate for real mountains. Being the engineering type, I figured out how it could be done. Triple chainring, a 2-cog "dingle on one side of a flip-flop hub, a tiny single on the other; all cogs on chainlines for their specific chainring. All 1/8". Had TiCycles make me the "dingle" and some custom extra long chainring bolts.
Net result? A fix gear with true mountain gearing, 46-12 or lower high gear, 44 or 42-17 flat ground and 38 or 36-21 uphill with the capability of going as low as 36-24 for uphill gravel carrying a chainwhip (I'd already made a 16 oz aluminum chainwhip for past Cycle Oregons) Bike could be set up with a 35c tire in back and bigger in front. Last August, I rode with a bunch of BF mates over the Trask River Trail on this rig. Worked beautifully. Yes, uphill WAS HARD! (Fell over once when I stalled on loose stuff at 19%.) But down through deep "gravel" of loose 1 1/2-2" rocks, the bike was absolutely sweet! Like this is what it was designed to do!
I've fallen completely in love with this bike again. Mo longer is it the compromise that desn't do anything well. It is still a compromise, but it is a compromise that can be ridden fix gear on any "road" that is. Those old pictures of racers with their fix gears in the '20s on bad unpaved roads? Put my Mooney there. And with the new, really good 28c tires, the ride on pavement as a fix gear is sublime. Really fun to ride long distances on. I'll probably attempt a 150 miler next eeummer on one of the long days. I was going to do 130 on a Century ride a few weeks ago but got nailed with a cold so I bailed and did it on my geared bike. Rats.
So, OP, my point in all this is seeking versatility from the start can pay dividends. Of course, a real part of this is - are you happy to sell or put aside what you have invested in when a new type of riding comes along? If so, maybe investing so much in an "all-arounder" might not be the smartest. For me, that Mooney is a huge part of my life. I had 40,000+ miles on it before I started this. It has helped me stay this side of jails, institutions and death. (Those crazy rides weren't about having fun.) To now find that application where this bike that I thought was destined to be 'number 6" and a good tourer if I ever decided to do that again is now suddenly one of my all-time faovite bikes! Wow!
Now, the decisions I made allow what the bike does now, but just barely. Tire fit in back with 35cs (big Paselas) is VERY close. I have to jam the tire into the chainstays to just get the axle past the dropout, chipping the dropout paint. The bike does not have bosses for racks on the seatstays but uses the older single brake bolt mount. Not a big issue since the bike has cantis so access there is great. (It does have LowRider bosses because setting up LowRiders with the U-bolts is such a pain.) Single fender eyes front and rear. (Brain engaging - I should talk to TiCycles about adding rack eyes prior to the paint job that is coming. They are already going to move the RD housing guide from alongside the chainstay to under so I don't hit it with my hub wrench. Also add a 3rd set of WB bosses.) So there are a lot of "just barely"s on the bike. But they work! Now the bike will probably evolve to a dual mode - one crankset, derailleurs, shifters (DT shifting makes this really easy) and rear wheel for gears and touring and as is for fix gear. I'd love to get the switch time down to say 20 minutes.
I guess my post could be titled "The Evolution of the 1979 Peter Mooney".
Ben