My son, and my daughter have both gone through ETC. My son is in the last ETC book 8, having gone through all the ETC books, including the Pre-ETC, Get Set, Get Ready, and Go for the Code. My daughter is 2 years younger and she is in ETC book 3. We have liked them. My children get very distracted with all the color and images in some workbooks, so the ETC books have been great for us. In my opinion, they are solidly phonics based and they are fun. There are sections of funny/silly sentences and stories they have to read, and this has caused us to laugh out loud.
I don’t think the ETC books would be a good phonics program on their own, but a good supplement for a phonics reading program. For my son, we used AlphaPhonics along with their readers and the BOB books for early readers. The ETC books went well with Alphaphonics.
For my daughter (dyslexic) we tried AlphaPhonics, but it DID NOT work for her, we had tears and frustration. so we are now using Reading Made Easy along with ETC and it is working great for her.