LifeReef have been around for a long time and the design has not changed. Most of the new Skimmers where like I said designed for market demand. People started to go small tanks and many new comers so stands and sumps became smaller and one of the biggest factors Electricity costs were rising, if there is any skimmer that one could say is a staple in the skimmer market I would have to say the Reef Octopus Classic 150 INT. Back when I started the Coral Life 5500 K bulb was all the rage with the 6500K being waited for with great expectations. Skimmers where large Down Draft monsters, I had one and you would swear it sucked the poop out of the fish before he had a chance to do it for himself, but they required large pumps that used up the Electricity and you add the MH lighting and some had chillers to cool the water because of the lighting the industry had to make something more efficient and that brings us up to modern day reefing in a nutshell. Many quit the hobby and many store closed and manufactures closed also.
The big top skimmers back then where AreoFoamer, HSA, AT Tech ( ETSS ), MTC and let's not forget LifeReef he was mixed in there. You could not go wrong with a LifeReef skimmer. If you would choose them, get the tallest that you can fit. you should check out YouTube you can see many of the skimmers in action. The other thing is a LifeReef will cost you more to run over the years of operation compared to say the Alpha.
You my friend have a big decision to make, I believe you may have narrowed it down to 2 makes and I myself would choose the Alpha 170 as your Total volume is 200 gal and once you add Rock and Substrate and factor in the fact the sump will only be roughly half way you will be at the 140 to 170 gal mark. the biggest thing I have found with the Vertex line of Skimmers is it takes time to fine tune, but when you do they perform. By fine tune I mean the air adjustment/ Flute on pump, probably the most important thing on them and most just don't bother or have the patience to take the time and work with it. The other thing they have going for them is the bubble size, they create some of the smallest bubble's I have seen, right there with BK and the old Turbo Floater skimmers from AquaMedic ( they used a true needle wheel ). Well getting long winded.
Good luck with your choice!
Oh ya, make sure to check and double check to make sure your choice will fit your Sump and Cabinet, it may should oddvious but you would be surprised how many skimmers you see for sale and reason for selling would not fit my sump or Cabinet.
Let us know what you choose.
Skim