2 is REALLY good but I love top gear 1 a little more although I think 2 is probably a little better. it was one of the few games I had growing up and I played it way more than anyone should have. I have never played the Amiga version, but when I found out most of Top gear was remastered lotus challenge tunes I had to go back and listen to all the soundtracks.
I also must say that overall the SNES and PC Engine are tied as far as sounds go for me. Also, i think the fact that the top gear sound tracks don't get credit as some of the best is also a little bit unfair. yeah, the RPG's and platformers may have some really great soundtracks but for a racing game top gear, 1 and 2 are among some of the best IMO.
Oh I get that, I love Top Gear 1 almost as much as the 2nd game, I might have even played it more, it's simpler and more approachable than Top Gear 2, and it's better for shorter play-sessions, but the 2nd game is for when you wanna get serious about it you know what I mean? In the 2nd game there's a career mode where you can earn cash to tune up your car and make it better as the races go so that you can keep up with your opponents who are also getting their cars better and better...
To put it simply, the 2nd game is deeper, it also has the advantage of taking up the entire screen in single player mode as opposed to having the screen split at all times, but the first game also has its own advantages, like having one more song to play throughout the races so there's less repetition (not like you'd get bored of listening to either of those amazing soundtracks) and having cars which look different from one-another whereas in the 2nd game every car model is the same, the only changes are in colour...
To be fair though, having only one car model has made them able to use the memory they had to make more sprites of that one model as opposed to less sprites of multiple models, and because of that the animations are better in the 2nd game, also the "Draw Distance" of the 2nd game is also way better, the Pseudo-3D road goes really far into the screen and you can see the curves approaching from way in the distance and it looks great!
As for the soundchips, other than my own nostalgia towards the SNES, what really settles it as my favourite is the fact that it's the perfect middle-ground in between chiptunes and 'real' music, the SPC700 is an 8 channel sampler, it's got enough channels to be able to make a full-bodied song and still have one or more channels left to play sound effects without clipping-off parts of the music, and because it's a sampler it means that it can play literally anything you can cram within 64KB! (Including instruments synthesised on the PCE or MD, which means you could potentially re-create any PCE/MD soundtrack on the SNES with little-to-no noticeable loss in detail or quality, but not many people did that because they could sample 'real' instruments instead, or instruments from a more sophisticate synthesiser)
The PCE is great too, it's my 2nd favourite for a very good reason, yeah it's got less channels, but the channels it does have are already enough to make a soundtrack just as full-bodied as any SNES soundtrack (as proven by me and by plenty of PCE composers from back in the day) it can play samples as well (albeit in a much more limited fashion than you can do on the SNES) and it's VERY easy to make awesome music for it! Although that's more thanks to Deflemask than anything, the SNES doesn't have a dedicated tracker, although I can make music for the SNES which will run in real hardware using OpenMPT, I've already stated time and time again how OpenMPT isn't great, and that Deflemask is SO much better in pretty much every way... But it's not just that, 5 bit wavetables are an extremely easy-to-understand-and-use method of sound synthesis, it's as simple as drawing whatever waveform you want and playing it on whatever note you want! The lower bit-depth makes it even easier to work with (albeit more limiting) because there's much less room for error when you only have a 32 x 32 grid to work with, but even with such limited synth they've managed to compose absolute masterpieces such as the Soldier Blade, Magical Chase and Xanadu 2 soundtracks~ (2 of which don't even use samples, they're all PCE synth)