The primary difference between the snorkel and foodsaver type sealers are the types of bags you can use. The foodsaver sucks from the edge of the bag or (with the newer handheld model) through a one way valve. To prevent the bag from collapsing around the suction and preventing complete evacuation, foodsaver bags are ribbed internally that allow air to flow even once they are fully collapsed. With a snorkle type vac, you push the snorkle into the bag which holds it open while it sucks the air out.
If you want use other bags, including resealing mylar bags, you have to go with a snorkel type vac. Snorklevac website warns that even then, to ensure complete evacuation, you have to have the contents of the bag as close to the snorkle as possible. I consider this a downside in that the vacuum might suck up the loose hop material, though I'd have to hear other's comments on this since I've never used one.
Interestingly, I just bought the handheld foodsaver that works with reusable bags: a huge bonus, IMHO. The bags seal with a ziplock type closure, then you press the unit to the outside where I one-way valve is located. No heat sealing, and you can reuse the bags. You can also get containers. The starter kit is reasonably priced at $29, but I got a deal on mine at $5! Seems to do a decent job.
Be interested in hearing other opinions and experiences as well. I'm sure some of these more expensive units can suck a pretty good vacuum, but realistically, you want to be using your hops relatively soon and definitely within the same year. So, it's not clear to me how important this really is. If you want to store hops long term, nitrogen evacuation is the ticket, and for this you need an expensive setup.