The low end Last Legend swords, Nohara Grade 1 of the 2000 series are thoroughly hardened and not differentially hardened.
Going up from there in the Last Legend swords you'll get the differentially hardened blades.
The cheapest Bugei sword is actually $963.00 without the shipping/handling included, which is the Shobu Zukuri model.
I've order the Crane from them which was $975.00 but totalled to $1,013.00 with the shipping/handling included.
It's the Wave model from them that costs $1,525.00.
If you get the Wave with a bo-hi then it'll come to $1,725.00. Both prices not including shipping/handling charges. The Wave model has the most customizable options of the whole Bugei line. So it's the Wave the would cost the most.
When it comes to production swords, I lean towards high end like Bugei or the high end lines of Last Legend.
Angus Trim came out with his line of Katana now. His heat treatment is supposedly really good. When it comes to swords, it's all about the quality of the head treatment.
Here's Angus's Japanese styled swords that should be considered as well. But of course check with your sensei.
http://www.atrimasa.com/Japaneseswords.html
His swords have some customizing options as well.
Bo-hi does take away some strength. But more importantly it's about the heat treatment that should be more of a concern. Bo-hi itself should only be selected by experienced practitioners of tameshigiri who's technique is consistant. If you're a beginner or intermediate, bo-hi is not recommended on a sword that'll be put to tameshigiri practice. For kata, bo-hi is fine since doing kata you're only cutting air.
Should read this article regarding niku and bo-hi.
http://www.bugei.com/niku.html