The only thing with squonking, if you find a squonker you like is you need to stock up on spares for it because with very little in the way of new squonkers coming out your stuck with what you have esp if you like it. As an example ive bought various spares for my topside dual including a few spare circuit boards, battery doors and bottles etc. I also like the Gbox squonker due to it's simplicity and it gives a very good squonk with that i was lucky to source 2 brand new Gbox kits recently at a good price so i know have a complete spare setup.
For any squonker the bottles are the issue esp the topside which takes a certain type of Topside specific bottle and the mod can't really be modded to take something else, those bottles are currently way overpriced for what they are as one will cost £11.99 GB, with the Gbox you can mod that one to take most aftermarket bottles as its easy to do, i actually like the Gbox firmer type bottle, the new genuine ones are not easy to find and if you do find them again they are overpriced for what they are so i bought a load from DHgate where a few sellers have them, not genuine Gbox but almost identical and probably came from the same factory in China.
