I use the megs stuff and water it down a little to make it more spreadable. I find it great on older rubber seals I have on some of the cars where they dry out and start to crack as I haven't found anything else that gets moisture back into them properly.

A lot of stuff seems to stick or sit on top for a bit but the megs I use seems great with a little paint brush to get it on  FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.