I've been playing this a lot the past few days and I am really impressed by all of the innovative features in this game from 1993, many of which were adopted by CAVE and Raizing later. Actually, the game reminds me of Pink Sweets in many respects:
-Some of the stage layouts are very similar (the cloud stage enemy designs and placements in Stage 6 are similar to Stage 6 in PS, for example).
-Descructible bullets on the bosses, which you can milk for points.
-The need to beat most of the game without dying for maximum scoring. In PS, this is necessary to trigger infinite lives. After you trigger that, you need to die a lot to score. In Gunnail, you die a lot in the first few stages, then have to no miss the rest, in order to score optimally.
It reminds me of Ibara with all the bombs you get, and the need to play most of the game without lives in stock. Some of the bosses remind me of bosses in Muchi Muchi Pork.
The multiplier tied to lives in stock (no lives = biggest multiplier) is the inverse of what we find in Futari Black Label (max lives + bombs = biggest multiplier), but it's the same basic idea (no miss the game, and you are rewarded with a huge bonus).
The PS4 port emulates the PCB's slowdown well, from what I have seen, and the options to have separate rapid fire buttons and turn off the stupid warning siren make this the best way to play the game, IMO (Save states for practice, and nice scanline options, too!). And it's only eight bucks! Input lag is fine, I'd guess it's around 4 frames.
