BPS dermacrine or Olympus labs Sup3r Dhea both are transdermal.
For the 35+ crowd, dermacrine is great. But for the younger crowd, I would advise against it unless someone is wanting to run it as a base.
When I choose a test booster, I don't really look for what will increase my libido. I look for something that will help me towards my physique goal(s). And that right there is the main reason why I have used many test boosters. Not for the libido, but to aid in my goals. I've done my research on ingredients, followed logs and looked at reviews. I make my decision with all of that in mind and take one product at a time for 8 weeks. I keep notes on what I do and don't like about each product. Once I have tried a few, I look to create a natty stack. I rule out products that overlapping ingredients wouldn't benefit me and I add products that I know work for ME and MY body.
Side note: Keep in mind that no supplement can replace diet and training. This has to be on point.
For example: when I'm looking to cut or recomp, I tend to gravitate towards a test booster that has worked for me in the past that also contains forskolin. If forskolin isn't an ingredient in any products I have tried, I buy it in bulk and add it to my stack. I also usually include ArA in nearly every stack I run except for when I'm logging a specific product (logging is a great way to try something without paying for it). Supplements can be expensive so it's always nice to find what you are looking for and log it. It also helps others.
That being said, my two favorite muscle builders that actually help me with my physique are AlphaMax XT and Anabeta Elite. Both are proven products that most people on this forum absolutely love. I've stacked them both one time and it was incredible.
For mass gains, it's a little bit harder to find a (natural) product for this. Usually, more calories = weight gain. Which is why appetite is important. There are ways around increasing appetite to get calories in (shakes, milk) but nothing can replace real food. Also, many test boosters (not all) have some form of estrogen control in them so it's harder to see mass gains with that unless diet is geared towards that goal. Right now I am using MassMax XT. On beginning of week 6 / 8 right now. Not stacking it with anything yet because this is my first time using it. My diet is clean bulk with 1 cheat day during the week. I have gained roughly 6 pounds so far. I will probably stack it with Anabeta Elite and ArA next.
I hope this helps.