The change from V21 to V23 is HUGE compared to V23 to V25. For 23-25 it is a slight bit different, but very easy to get used to. Given all the new toolpath options you get, I suspect you will benefit a lot from an upgrade. Make sure you drive for a good deal, the price is VERY flexible as always. As mentioned, the new Advanced Roughing option is an HSP-like toolpath generation, and may benefit you in machining time a good bit... You should ABSOLUTELY at least do the demo and check it out. If you do want to upgrade, I would wait for a call from BC rather than calling them, and then "play hardball" to get the price down. The worst that can happen is you don't buy then, and buy later. The best that can happen is you get a deal way better than you ever thought you could...
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