I have purchased a number of Catalyst published CBT products in the past few months and with one minor exception I have been surprisingly impressed with the overall quality of their products.
For an old Battletech hound like myself TechManual is an odd duck; simply put, in the past these rules were consolidated into other products.
1) If you wanted to know how to build mechs, tanks, or infantry go to the compendium.
2) If you want Aerospace or Dropships, well at one point you could do the compendium, but then they forked that product line and moved those to Aerospace 2 iirc.
3) I left the game before Protomechs were created and the only BattleArmor around were Toads; I don't see construction rules for them in my copies of the compendium or the BMR so I'm assuming they were in a separate product.
Additionally, as we all well know, FASA really liked to put individual products into non-consolidated sourcebooks. This as some may remember, lead to those wonderful times where building a unit would often require flipping through 2-3 books.
With all that in mind it is obviously very nice to see a compendium of unit construction rules like this one. You can find construction rules for every major type of unit used in Battltech as well as detailed descriptions of equipment, armor types, engines, etc.
I particularly enjoyed some of the fiction sections as they are informative and entertaining. The fiction section on Battle Armor, I found to be very entertaining for some reason. It also filled me in on a few details about those units that I had either forgotten or just did not know.
The presentation was great and the actual rules included were substantial. In both cases Catalyst has gone above and beyond what we used to get from the old crew at FASA. Their hardcover supplements simply look great, and the rules included have evolved over the past 25 years. The team at Catalyst has done a great job in shepherding this process, they genuinely care about this game, and it clearly shows.
I do have a few minor gripes; one of which is the length to which it seems they've gone to remove rules included in Total Warfare from this volume. I had a similar gripe about the rules in TechManual that were obviously omitted from Total Warfare. Specifically the equipment section in this book has zero information on actual gameplay rules about the equipment, outside of weight and crit slot requirements. I can easily see myself having to flip between the equipment sections of both this and Total Warfare to build a unit properly. That seems a bit silly. I would not have minded paying $5 more if some of that game data was included here. Regardless of it's possible redundancy.
All in all I think this is another incredible product from the Catalyst team. If you enjoyed FASA produced Battletech supplements, and haven't checked out the the Catalyst product line yet, you are simply missing out.