As someone who replaced a modified Strega with the Evo Leva, I can tell you a bit about them.
Main things of interest:
- HX machine as mentioned
- Vibe pump fills the group - so up to 9 bar or more
- Double spring lever group, capable of over 10 bar - I measured mine at something like 10.5 bar as I recall
- Heated group, which in standard trim has a 10C deadband thermoswitch, so group stability isn’t that good.
- Quick to warm up thanks to heated group - much the same as the Evo.
Best mod by far is a PID on the group. Immediately get group with adjustable temperature that is stable. Despite fiddling with the PID settings on my Evo, I still can’t get my Evo group quite as stable temperature-wise as I had on the Strega.
If you know a bit about wiring things, putting the PID on the Strega group isn’t hard as all. I used an auto-tune PID, case, solid state relay and sensor from Auber that cost less than $200. Hid the case under the machine - pulled out the water tray to adjust it. Didn’t need to cut a single wire.
I also put a PID on the main boiler - a deal harder to do as getting a temperature sensor to fit and the right sort is difficult. Not worth the effort really, as main boiler temperature has less of an impact on brew temperature than does the group temperature.
I tried a remote controlled solid state dimmer om the vibe pump to adjust pre-infusion. Sort of worked - did reduce pressure, but you couldn’t go too low as it also reduced flow considerably and the group took too long to fill.
In my view the only lever machine I have seen which was a step up from my modified Strega was the Evo. The heated groups gives you so much temperature flexibility (with PID), stability and the fast heat time, which no other lever machine can achieve.
So in summary, the Strega is a good value lever machine in stock trim, made excellent with a PID on the group cartridge heaters.