I would spend a few bucks and have a nice set of bronze guids installed and the good locking seals. The felpro kit seals are not very good. But on a buget yes they should be OK.
On my heads I also had the spring seats machined and then put in spring cups to hold the springs in place better. This also gives a more even and firmer surface to have the spring sitting on.
All this is done at the installed height reccomended by your cam/sring/valve combination.
PS if you are after a little more HP and going with new valves, then when you get the guides go with the 11/32 guides and slimer 11/32 valves(chevy type). This is only if you are putting a lot of $$$s in the heads.
