Depends. AS stated, the 1350 is a 1250 with the size profiling feature added. Wiser pundits than me have indicated that is a plus on beaches with lots of aluminum cans about.
Here's the real plus between them - the 1350 will accept any standard Garrett coil, and still give you the "profiling" function. It's been suggested that a 4.5" coil will be useful for those homesites which are likely to be iron and trash infested.
For around the same money NEW, why not get the profiling feature? Thats at stated discount prices, of course. Naturally, if you can find a deal, then go for what fits your budget. They are essentially the same detector.
I know of one dealer who has brand new 1250's for 428$. If you email, Ill tell you who that is. The 1350's are still gonna run $560 or so for awhile, as they are still new to the market.
(I got lucky and found a slightly used 1350 for a little less than new 1250 I spoke of - had the blank warranty card included. Maybe you can get lucky, too!).
I had a 1250 for awhile and found it to be very sensitive and a good discrim'nator. I think you could do alright with the uses you want it for.
David