READ IT!
The Saga of the (Pliocene) Exile(s) is one of my favourite series ever, really inventive, high excitement. Can be a little confusing in spots, but still awesome. I stole it off my Dad's bookshelf when I was a kid and loved it and have just finished an
Nth re-read (I didn't realise how lucky I was to find the full set in a second-hand book shop a few years ago).
I'd also recommend May's series set in the same Milieu (no pun intended, well maybe it was!) the Galactic Milieu Series. It's set in the future world from when the time portal back to the Pliocene is opened (though the time portal itself makes only a cameo appearance). To be honest, I think I love the Galactic Milieu Series even more than the Saga of the Exiles; I can't read the phrase
a scent of pine without a tear of bittersweet melancholy springing unbidden to my eye.
The only thing would be, I'm not sure which would be best read first? They're all intermingled in my head now. I think I read the Saga of the Exiles first, but can't be sure.
My advice would be to go out and scour the face of the Earth until you get all the books, then revel in them as I did/do:
Saga of the Exiles:
The Many-Coloured Land
The Golden Torc
The Non-Born King
The Adversary
Galactic Milieu Series:
Intervention (stand-alone, I think)
Jack the Bodiless
Diamond Mask
Magnificat