Since we are having a spa built into a shallow landing/beach area of the new pool the contractor has given us an option to have a negative/infinity edge effect on the spa at no charge. What are the negatives and positives of a negative edge spa? Can you still sit on the spa edge if it has a negative edge? The spa elevation is only about 3" above the pool water level and about 3/4 circle inside the water (Pool water is surrounding the spa by about 75% of the spa ledge area). The Contractor said that he would only put a 1" of rise in the 14" spa ledge. The pool sits between our house and the edge of a lake.