I can't recommend any particular shakes, however, if you spend a few hours doing comparisons/homework online, say dropping by low carb purveyors like Netrition or health food suppliers like GNC or even Amazon.com or Drugstore.com (who often have great deals on protein products), just use your copy/paste to set up a comparison chart (no matter how rudimentary).
Figure out which mix (you probably will get a better deal if you buy powders you MIX YOURSELF with water or Almond Breeze low carb beverage) will give you the comparable protein to carb to calories ratios.
It's cheaper to buy a big ole cannister of some protein mix (in a flavor you love) or two of them, and just make it yourself in a shaker cup or blender. You might even be able to warm up the chocolate flavored ones to get a hot choco protein drink. Worth experimenting.
It's easy to read reviews and see which ones taste good, etc.
I've enjoyed the BSN Dessert Lean ones (that are lower carb than their others). Let me get one from my kithen: My CINNAMON ROLL flavored one-- it's 130 calories per scoop, 3 grams of fat, 20 grams of protein, 7 g of carbs. So, it's a lot more protein--5 grams more-- but 30 more calories more, too. A bit more fat, but the SAME carbs (so the protein to carb ratio is actually BETTER). My cannister (smaller than the Synta 6) cost me 20 bucks (though I used a coupon code I had for Drugstore.com and got it cheaper). It has 18 servings. However, you can use a bit less per scoop since you can reduce calories and get very, very close to Wonderslim's numbers. That would take you to more than 18 servings, maybe 20, and it would mean about a buck per serving. Less than Wonderslim, which is 7 packets for 10 bucks. I have it in chocolate coconut, Cinnamon Roll, and Banana Pudding. I like all those flavors. This is one of the tastier protein mixes I've tried.
Designer Whey is worth checking out. (Avoid Muscle Milk, as it was documented as highly contaminated with toxic metals by Consumer Reports.)
If you do that comparison for other brands, you can make a decision.
It's not hard to compare. It's just a matter of taking the time, really.
I hope you find something you LOVE LOVE LOVE (and look out for when coupons for WonderSlim crop up, cause I got 15% off my first order by using a coupon that was only good for ONE day that I found by luck). Just set up a Google Alert for the coupons for that provider or product specifically and Google can send you a daily alert. It can't hurt.
Ya might get lucky and catch a day with a nice big discount.