Hey Toast - first thing I got was a mask and I only went and played paintball a few times a year at that point (couple of years back) - the fact that you can actually see stuff makes the biggest difference in my opinion so any investment is worth it
. I have Empire E-Flexes for mashalling (as they are so comfy) and Grills when I play - both have their advantages and disadvantages - same goes for any mask!
If you are in the Canterbury area still, Quex Park Paintball near Margate (about a 20 minute drive) can accommodate you if you 're worried about renting some kit (like a bottle). I'm not sure what the Mayhem policy is now with own kit (Canterbury site), but Quex Park are very friendly towards those with their own gear and will always allow you to use it subject to the chrono tests
. If you have a loader, then again, you can use that with a rental marker