Considering adding a lift - thoughts on 2-post vs. 4-post?

Looked at lifts 2/4 post..... my pole barn 40x30 is multi use/storage//marginal ceiling height //really didn't want to commit to a perm fixture/ I have trans jack/engine lifts ect///went with the 7000lb quick jack by bend pack/does everything I needed to do including// lifting my 6500lb empty f350///5700lb dodge 1500 van and NOT hitting doors like a 2 post lifts!!! plus my version is the 110 volt Portable with a generator!!!!!!!!!!!!