I worked in downtown Dallas for several years. Have lived in Dallas area for 30+ years before going full-time, and with kids/ grandkids in the area still visit often.
I WILL NOT take I-35E from downtown Dallas with my truck/TT. I do take US-75->I-45->I-20->I-35E often. An easier, straight shot past downtown Dallas. The I-35E / I-30 Interchange requires too many lane changes too fast.
Taking the straight route vs I-635/I-20 loop depends upon time of day. Both roads are subject to rush hour delays. The straight thru has fewer non-freeway options if you get caught behind a backup. The Loop has more lanes and is quicker to clear accidents than the straight thru route.
The one thing to watch is where I-635 ends and becomes I-20. Be in the left lane when you get to the I-635/I-20 intersection. Watch for idiots on I-20 trying to cross five lanes of traffic from the far left to the far right in 1/3 mile to make the US-175 to Dallas exit.
The loop is less stressful for most folks.
Recommended times are between 10 am and 3 pm. Or before 7 am / after 7 pm.
Construction on US-75 north of Dallas is minimal delays through Allen/ Plano.
Construction on I-35 near Temple gets tight about 5 miles north of Temple and continues past Belton.
Nothing major, just no shoulders and 'small' lanes.
Full-Time 2014 - ????
โNot all who wander are lost.โ
"You were supposed to turn back at the last street."
2012 Ram 2500 Mega Cab
2014 Flagstaff 832IKBS TT