The Artifex are sometimes a little thicker behind the edge due to the style of the grind and will need some thinning out if you want more performance out of it, especially in root veggies. If you're in the US, PM me and mail me the Artifex and I will thin and sharpen it for no charge and you can see if it works better for you.
As for other stainless Western handled knives, there are lots! Root vegetables can be a royal PITA for many knives to cut though. There are two schools of thought on the subject. One is to get a knife known as a Laser (thin gyuto). The thinner blade will encounter less resistance through root veggies, but may flex more. The other school of thought is a "mighty" gyuto or Western Deba. This is a thicker/heavier gyuto that have more convexing to the sides of the blade that will help push the food apart as it cuts and the heavier weight helps keeps the cut going.
Another option may be a Nakiri, depending on the size of the food you are cutting. These are double beveled knives that look like a short Chinese style cleaver, but are very thin. I use Nakiri's on potatoes and carrots a lot, as well as onions, mushrooms, etc. Great veggie knives, but the blade may be a bit short for going thru big squash and stuff as most of these have a blade around 6-6.5" long.
I haven't cut many root veggies other than potatoes (sweet and regular) and carrots. The gyuto that I have that does the best is my Tanaka Sekiso 240mm Damascus gyuto, but it's carbon and Wa handled. It outcuts everything else I have tried in sweet potatoes, including my Nakiri's and reground Artifex, Addicts, Kikuichi's, etc. The reground Addict and Artifex probably take second place to the Tanaka. It has a nice convex blade grind to it and it's crazy thin behind the edge.
For gyuto's to consider, I am going to throw these suggestions out there (stainless, western handled and under $200) and see if anyone has used them extensively on root veg to see how they perform. I have used some of these, but not much on root veggies to know how they will actually perform. Hopefully some of the guys here can chime in and fill you in! Also, look for some videos of these knives; many guys like to cut potatoes to show how they do in that root veg.
Hiromoto G3 series:http://www.chefknivestogo.com/hig3gstkn.html
Tojiro DP Gyuto or Western Deba:http://www.chefknivestogo.com/tojirodpseries.html
Fujiwara FKM Stainless:http://www.chefknivestogo.com/fufkmse.html
Sakai Takayuki Grand Chef:http://www.chefknivestogo.com/grandchef.html
This one has a Wa handle, but may work well:http://www.chefknivestogo.com/satadagy240.html
Mark also has a few M390 Artifex that I reground and rehandled that may work as well.