I tried Meguiars Ultimate Compound on mine and to be honest I didn't think it did much, however people rave about it. I think with the Megs and G3, they don't work well just done by hand - probably need a Dual Action buffer to get full effect. Looking to buy one myself.
g3 is a watered down mess, i think its the design of the bottle that makes people think its any good
from the consumer range, megs ultimate compound is the best any joe bloggs off the street can buy, can be used by hand or machine, clearly youll do a better job by machine, its also worth noting, that even this is slightly 'watered down' to be consumer 'idiot' friendly
but as williamcorsa has stated, if youre going down the machine route 105 and 205 will be youre best bet, however also remember to use the necessary pads to each product
Well there are many scratch remover in the market, but first you have to check that how deep the scratch is? because if scratch is very deep then you need to repaint that area but if its on upper surface then you can use any scratch remove to remove that scratch.