I used to have them

.
They make great pets IMO but I can't compare them to fancies since I've never had them.
Spiny mice can be tamed but they are definitely not domestic animals. They are not cuddly pets and some can be rather mouthy. I've handled several and had two of my own. Both of mine were friendly and would leap out of the tank when I opened the top. However, one was a bit nippy and didn't like feeling restrained or confined. The other was a complete sweetheart and enjoyed being pet. They both loved to play and run around.
They can be wild and are difficult to catch if they get loose, lol. The trick is finding a
reputable breeder who handles their mice on a regular basis. You do NOT want to get ones from a petstore who doesn't socialize their animals. It can be difficult to tame wild adults...but not impossible.
Now on to the positives

. They are intelligent animals who can learn their names, come when called, use a litterbox, etc. Spiny mice learn very quickly and can be taught games and tricks. Spiny mice aren't as smelly as fancy mice or hamsters. Also, once you gain their trust most will bond closely to you... some even groom their owners. Spinies live longer then regular mice, too, which is a plus. And because they aren't mass bred like fancies they don't have a ton of genetic problems.
It's important that you feed a good diet. Spiny mice need a diet high in protein and fiber but low in fat and sugar. It's not a good idea to feed a ton of calcium, either. High-quality
lab blocks are a good staple but they should get other foods too. I made sure to feed high-protein foods like eggs, Innova dog food, chicken, and gut-loaded crickets (they love hunting insects). Mine also got small amounts of fresh vegetables and an occasional nut or piece of bread as a treat.
You'll want to keep them in a tank since many spinies will chew through plastic. They are escape artists

. Since they are smart and active animals keep them entertained with lots of toys and let them out daily. Mine were let out at least twice a day. The first time they would get to explore an enclosed area or the bathtub...I'd hide food and provide lots of toys and things to climb on. Afterwards I'd handle them and give them each a small treat. Later on they'd be let out again and this time they would usually run around in their exercise balls and afterwards I'd give them a little attention before bed.
Here is a great website:
Spiny Mouse Care Basics