Opinions on a Second Telescope

You are right, they are the exact same sharpstar scope sold under 2 brands. It comes down to color preference or availability ;) 
Is it the only or best option? Depends. They both offer very good value to price ratio, so if you want a 4" quadruplet it's a very good choice. 
That said, there are cheaper options and there are better options. One thing I'd consider is that for the same price you can get the Askar 120 apo with corrector and for not much more you can get the 140 apo! The 140 may be a bit of a challenge for the mounts you have, but people do use it with eq6-r with some success, especially with the 0.8 reducer.  
​​​​​While the apo series are triplets, they offer (in my subjective opinion) even better value to price ratio. And while optical sharpness is of course a bit worse, it's still excellent for the price and the mechanical parts are top notch. 

​​​​​One more consideration is that you already have a 4" refractor, and while getting a double - Ed quadruplet would be an upgrade, going up an inch would be a much more noticeable upgrade ;) 

Disclaimer: all the info I presented above comes from hours and hours of research and talking to people who had these scopes, watching images taken with them etc. This all lead me to buying the Askar 140 apo which I literally acquired yesterday so I can't share any first-hand opinions as of now.

I don't disagree  
But!
While the phq scopes are excellent, the dedicated reducers seem to not be that great. According to the reviews I saw, they introduce visible CA which is a disgrace and basically nullifies the point of getting a scope that expensive. 
Also, the reducers require precise backfocus, which (again) nullifies the point of getting a corrected quadruplet. 
And let me reemphasize - it definitely is an upgrade and it's an excellent apo. I just consider an "almost as good" and noticeably larger telescope as a more significant upgrade  
It all comes down to personal preferences, there is no one right answer

I'm sorry to add confusion to the choice 😅 All I can say is that I was facing basically the identical decision you're facing now. I wanted to get the 130phq badly, but then with all the research I did and weighing pros and cons I decided to get the 140apo instead

Juan Pablo De la Cruz:
You all bring up some great points—thanks!Fortunately, I have a good two weeks to make the decision.@Jan Ossowski, the ASKAR 120 APO has now caught my attention. It’s more affordable, includes the focal reducer, and has a larger aperture. I’m also trying to find that sweet spot without getting into “back-breaker” territory, since I don’t have a permanent setup yet and will be carrying equipment around for a while. So, now I’m in “review search” mode. :

I own a 120mm refractor and it's definitely not a back breaker, unless you have a long way to carry.

I'll add one more detail. The 120 apo weighs 6.5 kg while the 107 phq weighs 6.9 kg 😅
(Apples to apples, both weights include the dovetails and rings). 
Yes, the apo needs a corrector which probably adds 500-900g or so but it's still basically the same weight.