another silverline user. should be getting my makita soon though. mainly because i do part time detailing at weekends. the silverline has been fine so far. i was using the porta cable until some scumbag nicked it out of my boot. DA machines are a much safer way for the amatuer to correct their paint. mainly due to the lower temps reached by the polishing head in contact with the paint surface compared to a rotary. It's also easier to get a more refined finish without tonnes of practise. it's a myth that you can't get as good a finish with them compared to a rotary.

before using a rotary on your car, get yourself a scrap pannel and practise like mad. i'll almost guarentee that you'll get buffer trails to start with and wonder why and then have a bit of trouble getting them out. it takes a huge amount of practise and product knoledge to get 100% correction that's blemish free.

another thing to consider is don't scrimp on the pads and polishes. if using a rotary the 3m pads and polishes are superb. menzerna polishes coupled with lake and country ccs pads are also spot on. get a good flexible backing plate to help with transitions over the curves of pannels.

main thing is, take your time, do your prep work properly and it'll make a huge difference to the out come. overall enjoy it. if you don't then it'll reflect (pardon the pun) in the end result.