We are currently using the American Deluxe trampoline my parents purchased in the late 80s. The only thing they had replaced is the pad (springs installed wrong).
We were given a jumpking enclosure and have replaced the pads, netting and brackets due to wear from two previous owners.
For safety issues, one thing to consider is a trampoline with a "double" jumping surface which reduces the the "double bounce" effect-I've seen it at a friend's house, she likes it.
Check with insurance, some companies will cancel.
In all the years my siblings and I have jumped on this trampoline and now as my children jump on this trampoline, we have not seen anything more than a scrape (falling off-before enclosure) or a bump and my kids get that from other play as well.
Good luck.