If your dealers are slow, and you are running a raked cash game then a shuffler will be worth the money, if the game runs enough times, in the long run, provided you take care if it. ALWAYS use good/newer cards.
Make sure your dealers treat them with respect, and use them correctly.
We run several at our poker rooms (not this brand) but we rent them, which is something you can consider doing, and if you dont like it then stop renting it. (depending on where you live this may be easy or difficult). I like them for several reasons, not as much stress on the hands, instant switching of decks, and a few extra hands per down.
Cost analysis: first off if you are just getting it for the novelty or relieving dealer stress then fine just buy one, but if you want it to make more money then consider this. You are only going to gain 2-3 hands per 30m down whether your dealer is good or bad, and depending on your rake rules and how crazy your game is, on the high side you will earn an extra $14 per hour. If your game runs 10hrs a session you are at $140 extra per session, at 4 sessions a month thats $560. So at this pace it takes you a 2 months to pay off their standard shuffler, the right cards to use, and the shipping and what not, but this is the high end of everything.
Also be prepared that if you dont like it or ruin it your table will be forever compromised from the install