"Here is the perfect place."
Translation:Jen la perfekta loko.
They are similar, sometimes interchangeable but not synonyms. “Jen” implies some way of presenting something, pointing towards it. And since you normally point at something a bit distant from you the “ĉi” would not always be adequate.
For instance if a friend visited you on a campground in your tent and asked you why you chose this place for your tent you might answer: *Ĉi tie estas la perfekta loko." You are not presenting anything, just talking about your campground site.
When you arrived at the campground with another friend you might have seen that place from a distance and told your travel companion “Jen la perfekta loko,” pointing at it with your finger. You are not there yet but you can see it.
I'd understand a perfektejo as a place where things are perfect or a place for perfect things, not as a place which is in itself perfect (= perfekta ejo, perfekta loko).
In general I think that -ej- fits best on noun or verb roots, to describe a place where the noun is found (e.g. malsanulejo "hospital, place where sick people are found, place for sick people") or the action is done (e.g. lernejo "school, place where learning takes place, place for learning").