Apart from a particularly annoying traffic jam where they all inched forward for several minutes (which I could have passed if in the mood), the gears are great. I don't think the original 1st would have been any advantage though.
1st is now a usable driving gear and not just to pull off.
2nd can be used between islands, zebra crossings and other slowdowns about town.
3rd is fine for 40 limits and fast islands.
4th for 50 or 60 limits (about the same as 5th was).
5th now very relaxing at motorway speeds with plenty in reserve.
As regards acceleration, it's probably quicker - as I'm not always looking for the next gear. They can actually be driven out. I surprised some cage drivers coming on to the A1 last night - changing up about 5,000 RPM the forks were rising noticeably and merging from 30MPH to 70MPH took no time and I wasn't messing with gear changes to do it. Old 1980s 'A' reg bike with obviously middle-aged (I wish) biker on board with a quiet exhaust

With the shortened left peg mount, what gear changes I make are positive and clean.