Our primary instructor (Dick) has over 5,000 hours flight time with at least 3,500 of those hours of instruction. He is a multi-engine and instrument instructor and by career education is a BS, MS, PhD Chemical Engineer (29.4 year career). Other instructors available from ALS Services, Inc. are also well experienced.
One caution, many schools operate with very young, inexperienced flight instructors (and maybe charge a little less). That doesn't mean they aren't good instructors, but, in many cases they are instructing to build flight time to qualify for an airline position and therefore may or may not have quality flight instruction as a personal objective. It is important that your instructor have enough experience to determine the methods of teaching that will help you to advance as quickly and inexpensively as possible.
ALS Services, Inc., a Texas Corporation, has been in existence since 1977 and has up to 3 aircraft online and available for training purposes. At least 100 candidates have been trained and obtained certificates and ratings from Private Pilot to Multi-Engine Instrument Instructor over those years of training. Examination failure rate for all candidates combined has been less than a 5 per cent rate. National flight schools combined rates of failure are substantially higher than that.